﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Demo
{
    class Program
    {
        static void Main(string[] args)
        {
            Mianji mj = new Mianji();
            Console.WriteLine("长方形的面积为"+mj.Sum(3,5));
            Console.WriteLine("圆形的面积为"+mj.Sum(3));
        }


    }
}
